From 1043e121320a01c07a77ff7e4eb4985777ca3c8e Mon Sep 17 00:00:00 2001
From: luckylooky2 <luckylooky2@naver.com>
Date: Tue, 21 May 2024 09:11:18 +0900
Subject: [PATCH] =?UTF-8?q?5.21:=20floyd,=20graph,=20shortest=20path(?=
 =?UTF-8?q?=ED=8C=8C=ED=8B=B0)?=
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---
 baekjoon/1238.js | 46 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 46 insertions(+)
 create mode 100644 baekjoon/1238.js

diff --git a/baekjoon/1238.js b/baekjoon/1238.js
new file mode 100644
index 0000000..c697772
--- /dev/null
+++ b/baekjoon/1238.js
@@ -0,0 +1,46 @@
+// 파티 : 최단 경로, 그래프
+const input = require("fs")
+  .readFileSync("/dev/stdin")
+  .toString()
+  .trim()
+  .split("\n")
+  .map((v) => v.split(" ").map((v) => Number(v)));
+const [n, m, x] = input.shift();
+const edges = input;
+const times = new Array(n + 1)
+  .fill(null)
+  .map(() => new Array(n + 1).fill(Infinity));
+
+for (const [start, end, time] of edges) {
+  times[start][end] = time;
+}
+
+// j -> i -> k(i -> j -> k가 아님)
+for (let layover = 1; layover <= n; layover++) {
+  for (let start = 1; start <= n; start++) {
+    for (let end = 1; end <= n; end++) {
+      //   times[layover][end] = Math.min(times[layover][end], times[layover][start] + times[start][end]);
+      times[start][end] = Math.min(
+        times[start][end],
+        times[start][layover] + times[layover][end]
+      );
+    }
+  }
+}
+
+let max = 0;
+for (let i = 1; i <= n; i++) {
+  if (i === x) {
+    continue;
+  }
+  max = Math.max(max, times[i][x] + times[x][i]);
+}
+
+console.log(max);
+
+// n이 최대 1000이기 때문에 다익스트라, 플로이드 어느 것을 사용해도 됨
+
+// i -> j -> k : i에서 j를 거쳐 k로 가는 방법
+// j -> i -> k : j에서 i를 거쳐 k로 가는 방법(이게 정답, 헷갈리지 않게 주의)
+
+// i, j, k 대신 layover, start, end로 기억하기